368 



stripe with a short brown streak on its posterior third, at middle of 

 disc; pleurae yellowish on central upper half, on other portions as 

 disc of menosotum; scutelliim and postnotiim as disc of mesonotum. 

 Abdomen with the apical half of each segment yellowish, covered 

 with whitish dust, the black portion produced posteriorly in the form 

 of a short point at center. Legs obscurely yellow, apices of all femora 

 broadly and of tibise and tarsal joints narrowly brown. Wings 

 slightly grayish; veins yellow; cross vein very distinctly blackened. 

 Halteres whitish. 



Antenna as long as from cross vein to apex of wing, the fifteenth 

 joint nearly twice as long as the rest of the fiagellum, second joint 

 very large; frontal tubercles absent. Mesonotum with brownish 

 yellow hairs on the spaces between the vittse ; a conspicuous group 

 of hairs in front of the wing-base ; a group of hairs on pleura above 

 and between fore and mid coxae (sternopleura) ; scutellar hairs nu- 

 merous and rather long. Apical portion of lateral arm of hypopygium 

 whitish, slender, and thornlike (PI. XXVIII, Fig. 2). Legs long, 

 short-haired, basal joint of fore tarsus almost as long as the remain- 

 ing joints together ; fourth tarsal joint of all legs longer than fifth. 

 Costa reaching almost to apex of wing, cross vein at middle ; cubitus 

 forking distinctly before cross vein ; surface hairs distinct but not very 

 numerous, pale in color. 



Length, 5 mm. 



Female. — Similar in coloration to the male. 



The antenna has the basal joint smaller than in the male, and the 

 hairs are only of moderate length; palpi with the basal joint slightly 

 tliickened, second joint thicker than first and subequal in length, third 

 joint almost as long as first and second together and slender, apical 

 joint slender, subecjual in length to second. Thorax haired as in male 

 though the hairs are rather more conspicuous. Abdomen with the 

 surface covered with rather long pale hairs. Legs rather stouter than 

 in male, proportions of tarsi similar to those of the male. Wing sur- 

 face very densely covered with brownish yellow iiairs ; cross vein 

 very distinctly blackened ; costa reaching almost to wing-tip, curved 

 v;ell round the margin ; cross vein very slightly before middle. 



Length, 4.5 mm. 



Illinois localities : Urbana, May 20. 1906, one male and one female ; 

 Muncie, Dubois, Grand Tower, and Golconda, April and May, 19 14. 

 Specimens taken by C. A. Hart and the writer. 



The female of this species was originally described from Maine by 

 Loew, and as far as I am aware has hitherto been recorded but twice 

 since — by Fyles, from Quebec, Canada, and by Johannsen. This is 



